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CHAPTER 34 • Glenohumeral Instability

an 80% recurrence rate in the nonoperative group and a 14% recurrence rate in the operative group at an average follow-up of almost 3 years. Bottoni et al. 26 performed a randomized controlled trial comparing nonoperative sling management versus early arthroscopic Bankart repair for young athletes with first-time anterior shoulder dislocations. At an average 36-months fol- low-up, 75% of patients treated nonoperatively had recurrent instability versus 11.1% in the arthroscopic stabilization group. Robinson et al. 192 prospectively followed 252 patients less than 35 years old, who sustained an anterior glenohumeral disloca- tion. Patients were treated with sling immobilization followed by a physical therapy program. Recurrent instability developed in 55.7% of the shoulders within the first 2 years and increased to 66.8% at 5-year follow-up. Younger male patients were most at risk of recurrent anterior instability. Jakobsen et al. 110 eval- uated patients, although not specifically athletes, aged 15 to 39 years after a first-time anterior shoulder dislocation. Patients underwent arthroscopy to characterize the labral damage and then were randomized to nonoperative treatment versus open Bankart repair. Patients then went through an identical rehabil- itation program consisting of a sling for 1 week and then initia- tion of motion. After 8 years of follow-up, 74% of patients who were treated without surgical repair had unsatisfactory results, whereas 72% of surgically repaired patients had good or excel- lent results. Itoi et al. 109 popularized the idea of external rotation bracing for the management of patients with acute anterior shoulder dislocation. In an MRI study, Itoi et al. 109 reported that immo- bilization of the arm in external rotation better approximates the Bankart lesion to the glenoid neck than does the conven- tional position of internal rotation. A subsequent prospective clinical study of 40 patients with acute shoulder dislocations immobilized in either internal or external rotation showed a significant difference in the rate of recurrence in patients under the age of 30 years. In the external rotation group, the recur- rence rate was 0% compared to the internal rotation group of 45% with a mean follow-up of 15.5 months. 105 However, sev- eral recent trials have shown no difference in the recurrence rates based on the type of immobilization. In a meta-analysis of randomized controlled trials evaluating immobilization in external rotation versus internal rotation after primary ante- rior shoulder instability in 632 patients, the authors found no significant difference in the recurrence rate, rate of compli- ance, and in the patient’s own perceptions of their health-re- lated quality of life. 263 Outcomes of nonoperative treatment in patients with MDI have been reported by several authors. Burkhead and Rock- wood initially reported a specific physical therapy program for patients with MDI. 33 Of the 66 patients diagnosed with MDI after an atraumatic subluxation, 53 (80%) had successful non- operative treatment. Misamore et al. evaluated the long-term outcomes of patients with MDI treated with a nonoperative physical therapy regimen. 155 The mean age at presentation was 18.6 years and almost all of the patients participated in athletics. Of the initial 59 patients, 20 underwent surgery by the 2-year mark. Of the remaining 39 patients, 19 continued to complain of significant pain and 18 continued to experience significant

instability. Patients were followed until the 7- to 10-year mark, at which 17 of the original 59 had a satisfactory outcome. They concluded a poor response to nonoperative treatment of MDI in this young, athletic population. Ide et al. 101 reported on 46 patients, mean age of 20 years old, with MDI who were treated with an 8-week shoulder-strengthening exercise program as well as an orthosis for scapular stabilization. They found improved outcome scores and improved mean peak torque of internal and external rotations. After a mean follow-up of 7 years, only 3/46 patients (6%) underwent surgical treatment. Randomized studies are difficult to perform on this patient population as it is universally accepted that nonoperative meth- ods should be the initial treatment in all MDI patients. Certain studies have looked at the outcome of surgically treated patients versus those who have solely undergone physical therapy 124 ; however, there are inherent biases in these studies, and it is difficult to ascertain how the information can be applied to cur- rent practice. Early surgical stabilization after traumatic anterior shoulder instability injuries has been shown to reduce the frequency of recurrent instability and improve functional outcome in young individuals engaged in physical activities. 118,123 The overall goal of surgical treatment for anterior shoulder insta- bility is to restore glenohumeral stability through either repair of the capsuloligamentous complex and/or enhanced stabil- ity through bony augmentation in cases of significant anterior glenoid deficiency. Open Bankart repair was previously considered the gold standard for treatment of traumatic anterior shoulder instabil- ity with recurrence rates of typically less than 10%. 40,90,165,197 The advantages of open surgery include a more secure repair, a greater ability to reduce capsular redundancy, and achieving adequate tension of the capsuloligamentous complex, which may be challenging in chronic instability cases. 39 The known disadvantages of open Bankart repair include restriction of glenohumeral motion following surgery, particularly external rotation, which may lead to secondary arthritis and muscle weakness. 40,90,191,197,244 As a result of the potential morbidity involved in open Bankart repair and improvement in implant and instrumen- tation, arthroscopic Bankart repair has supplanted open repair as the treatment of choice for most common anterior insta- bility injuries. 177,276 Arthroscopic Bankart repairs are increas- ingly performed. An assessment of the 2004 to 2009 U.S. national insurance database showed that arthroscopic Bankart repairs accounted for 84% of shoulder stabilization surger- ies. 276 Arthroscopic Bankart repair can minimize much of the morbidity associated with open surgery such as subscapularis weakness with possible rupture and arthrofibrosis. Modern techniques utilizing suture anchors and capsular plication have achieved recurrence rates similar to open repairs of 8% to 11% in selected patients. In addition to paying attention to the technical aspects of the arthroscopic repair, patient selec- tion, including careful consideration of patient and injury OPERATIVE TREATMENT OF GLENOHUMERAL INSTABILITY